Klun G, Fonda A, Sfecci A. On Dini derivatives of real functions.; 2021.

Fonda A, Klun G, Sfecci A. Non-well-ordered lower and upper solutions for semilinear systems of PDEs. Communications in Contemporary MathematicsCommunications in Contemporary Mathematics [Internet]. 2021  :2150080. Available from: https://doi.org/10.1142/S0219199721500802

Fonda A, Klun G, Sfecci A. Periodic Solutions of Second-Order Differential Equations in Hilbert Spaces.  [Internet]. 2021  ;18(5):223. Available from: https://doi.org/10.1007/s00009-021-01857-8

Fonda A, Klun G, Sfecci A. Well-Ordered and Non-Well-Ordered Lower and Upper Solutions for Periodic Planar Systems. Advanced Nonlinear Studies [Internet]. 2021  ;21(2):397 - 419. Available from: https://doi.org/10.1515/ans-2021-2117

Fonda A, Klun G, Sfecci A. Periodic solutions of nearly integrable Hamiltonian systems bifurcating from infinite-dimensional tori. NONLINEAR ANALYSIS [Internet]. 2020  . Available from: https://doi.org/10.1016/j.na.2019.111720

Fonda A, Klun G. On the topological degree of planar maps avoiding normal cones. TOPOLOGICAL METHODS IN NONLINEAR ANALYSIS [Internet]. 2019  ;53:825-845. Available from: http://dx.doi.org/10.12775/TMNA.2019.034

Fonda A, Gidoni P. An avoiding cones condition for the Poincaré?Birkhoff Theorem. Journal of Differential Equations [Internet]. 2017  ;262:1064 - 1084. Available from: http://www.sciencedirect.com/science/article/pii/S0022039616303278

Fonda A, Gidoni P. Generalizing the Poincaré?Miranda theorem: the avoiding cones condition. Annali di Matematica Pura ed Applicata (1923 -) [Internet]. 2016  ;195:1347?1371. Available from: https://doi.org/10.1007/s10231-015-0519-6

Fonda A, Garrione M, Gidoni P. Periodic perturbations of Hamiltonian systems. Advances in Nonlinear Analysis. 2016  ;5:367?382.

Fonda A, Gidoni P. A permanence theorem for local dynamical systems. Nonlinear Analysis: Theory, Methods & Applications [Internet]. 2015  ;121:73 - 81. Available from: http://www.sciencedirect.com/science/article/pii/S0362546X14003332

Fonda A, Garrione M. Generalized Sturm-Liouville boundary conditions for first order differential systems in the plane. Topol. Methods Nonlinear Anal. [Internet]. 2013  ;42:293?325. Available from: https://projecteuclid.org:443/euclid.tmna/1461248981

Fonda A, Sfecci A. Periodic bouncing solutions for nonlinear impact oscillators. Advanced Nonlinear Studies. 2013  ;13:179?189.

Fonda A, Sfecci A. A general method for the existence of periodic solutions of differential systems in the plane. Journal of Differential Equations [Internet]. 2012  ;252:1369 - 1391. Available from: http://www.sciencedirect.com/science/article/pii/S0022039611003196

Fonda A, Sfecci A. Periodic solutions of a system of coupled oscillators with one-sided superlinear retraction forces. Differential Integral Equations [Internet]. 2012  ;25:993?1010. Available from: https://projecteuclid.org:443/euclid.die/1356012248

Fonda A, Garrione M. Double resonance with Landesman?Lazer conditions for planar systems of ordinary differential equations. Journal of Differential Equations [Internet]. 2011  ;250:1052 - 1082. Available from: http://www.sciencedirect.com/science/article/pii/S0022039610002901

Fonda A, Garrione M. Nonlinear resonance: a comparison between Landesman-Lazer and Ahmad-Lazer-Paul conditions. Advanced Nonlinear Studies. 2011  ;11:391?404.